利用双节流元件测量两相流干度

The Measurement of Two-phase Flow Dryness by the Use of a Dual-throttle Element

以经典均相流和分相流模型为基础 ,推导了一个理想条件下直接测量两相流干度的公式 ,分析了公式的适用范围。设计了水平孔板和垂直下降文丘利管串联组合的实验装置 ,并以空气和水为工质进行了实验研究。实验研究表明 ,在环状流区垂直下降文丘利管的压降特性更接近于均相流模型的计算结果。这种方法在文中给定的干度范围内测量的相对误差小于± 10 %。

Based on a model of classical uniform phase flow and divided phase flow the authors have deduced a formula for the direct measurement of dual phase flow under an ideal condition. The applicable scope of usage of the formula is analyzed. An experimental device has been designed, which incorporates a horizontal orifice plate and a vertical descending Venturi tube connected in series. An experimental study was conducted with air and water serving as working mediums. The results of the study indicate that the pressure drop characteristics of the vertical descending Venturi tube in a ring shaped flow zone have been found to be more approximate to the calculation results of the uniform phase flow model. Under the proposed method the relative error of measurement within the range of dryness given in the paper is smaller than ±10%.